Preheat the oven to 350°F. Mix the oats and flour in a bowl. Melt the butter with the apple and pear juice in a saucepan; stir into the bowl.
Purée half the berries in a food processor; chop the rest. Mix the arrowroot with a little of the puree in a small saucepan, then add the rest of the purée. Heat gently until thickened, stirring, then stir in the chopped berries.
Spread half the oat crumble mixture over the bottom of a 7-inch round shallow baking dish to form a layer at least 1/2 inch thick. Top with the strawberry mixture, then the remaining crumble, patting it down gently. Bake the crunch for 30 minutes. Serve warm or cold, alone or with low-fat yogurt.
Important Note: Not all recipes offered here are appropriate for all people with diabetes. Please work with your health care provider, diabetes educator or dietitian to design a meal plan that's right for you.